Quercus lobata, commonly called the Valley oak, grows into the largest of North American oaks. It is endemic to California, growing in the hot interior valleys and foothills. Mature specimens may attain an age of up to 600 years. This deciduous oak requires year-round access to groundwater.

Its thick, ridged bark is characteristic and evokes alligator hide. The Valley oak's deeply lobed leaves assist in identification.

The sturdy trunk of the Valley oak may exceed two to three meters in diameter and its stature may surpass 30 meters in height. The branches have an irregular, spreading and arching appearance that produce a profound leafless silhouette in the clear winter sky. During Autumn leaves turn a yellow to light orange color but become brown during mid to late fall. In advancing age the branches assume a drooping characteristic. Its pewter-colored rippled bark adds to the attractive aesthetic of this species.

Typically, leaves are five to ten centimeters in length and are roundly and deeply lobed. The leaf width is approximately one half its length. Each leaf is matte green with an underneath pale green appearance; moreover, the leaf is covered with abundant soft fuzz, yielding an almost velvety feeling. When a fresh leaf is rubbed or broken, an aromatic scent is exuded, evoking a forest odor. The wood is a dull brown approaching yellow, and it has not been used extensively for milling.